This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The overall goal of this project is to improve the outcome of stem cell transplantation for patients with non-Hodgkin's lymphoma and acute leukemia by delivering supplemental radiation to target lymphohematopoietic tissues using radiolabeled monoclonal antibodies (radioimmunotherapy, RIT). The improvement of targeting methods may allow the delivery of larger doses of radioactivity from antibody to leukemia and lymphoma cells, while delivering lower radiation doses to normal organs, resulting in higher cure rates and less treatment-related toxicity. The specific aims in these non-human primate studies are: a. To evaluate the feasibility, safety, and toxicity of administering radiolabeled-biotinylated antibodies followed by extracorporeal adsorption in macaques. b. To assess the impact of extracorporeal adsorption therapy (ECAT) on the pharmacokinetics and biodistribution of radiolabeled-biotinylated antibodies in macaques.